Machine for making sandpaper and other abrasives



Oct. 8, 1940. w, BURNS 2,217,247

MACHINE FOR MAKING SANDPAPER AND OTHER ABRASIVES Filed July 7, 1930 2Sheets-Sheet 1 36 Fig. 7

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MACHINE FOR MAKING SANDPAPER AND OTHER ABRASIVES Filed July 7, 1950 2Sheets-Sheet 2 Fig. 5 gva/vento@ Wel/Z276?" BU/7705 attoznu Patentedot.s,194o 2,217,247

MACHINEv FOR MAKING SANDPAPER AND OTHER lABRASIVES Walker Burns, St.Paul, Minn., assignor, by direct and mesne assignments, to Behr-Ma.nning Corporation, Troy, N. Y., a corporation of vMassachusettsApplication July '7, 1930, Serial No. 466,124

3 Claims. (Clf 91-44) My invention relates to making sandpaper and outand which causes the abrasive material to other abrasives, where it isdesired to provide be projected against the sheet carrying the asheet-like material with an abrasive surface on abrasive. This may beaccomplished by` the one side, such as sandpaper, emery cloth andapparatus A which is provided with a casing 5 other abrasives, and toprovide a means for forming the enclosed compartment B in which makingthe sandpaper or other abrasives of a the table I0 is positioned. Thetable Ill is adapted more efficient nature and in a simple manner. tosupport an endless belt II which travels over A feature of my inventionresides in the means the driving pulley I2. The driving pulley I2 is formaking an abrasive material consisting in adapted to be operated by asuitable electrical l0 passing a sheet, which is coated with a bindermotor I3 which is positioned outside of the comw or adhesive substance,such as glue or varnish, partment B and which is connected by means ofpast an air operated means of blowing the ne a pulley I4 to the motorI3. particles of abrasive material against the sheet The belt II travelsin the direction of the so that the particles will stand out and projectarrow to extend over a blower -head C which ex- 16 from the sheet ratherthan lay down against tends` across between the sides of the table I03:; the same and pile or compact in relation to each and is of asufcient width to correspond to the other. This permits the surplusparticles of width of the belt II so that air maybe passed abrasivematerial to fall away from the surface from the blower head C throughthe belt II. to which the particles are to adhere to form the The blowerhead C is formed with an adjustable 20 sandpaper or abrasive material,rather than pile air outlet slot I5 which may be adjusted to the againstthe particles attached to the sheet to desired width so that air may beblown through k" make up the sandpaper, and thus the particles the slotI5 from the head C in a manner to force stand out like ne needles toform spaced abrasive air through the belt II. The belt II extendsparticles projecting from the sheet supporting the from the blower headC over the pulley I6 and same, and thereby providing a more eilicientdown and over the adjustable pulley I'I. The sandpaper or abrasivematerial than has been pulley I1 is carried by a diagonally extendingaccomplished heretofore in so far as I know. brace I8 and may beadjustable upon the same The features of primary importance will be totighten the belt II if it is desired so that the fully and clearlypointed out with those here proper tension may be maintained at alltimes before set forth and such others as form an upon the belt II. Anyother suitable belt adjustessential part of my invention. ing means. maybe EmDlOyed to keep the belt II In the drawings which I have illustratedto asat the deslred tension. sist in carrying out my method: Within thecompartment B, I provide a hopper Figure 1 is a diagrammatic side viewof an D for supporting a supply of abrasive material,

apparatus adaptable for carrying out my method. The hOPDel D iS formedwith an adjustable gate y 1g Figure 2 is a detail of a, portion 0f thesame, I9 so that the abrasive material may be uni- Figure 3 is a detailof another portion of the formly discharged out of the hopper, the samesame, running over the forwardly projecting shelf 20 Figure 4 is adiagrammatic plan view of a DOStOrled belOW the gate I9.

portion of the apparatus. In the lower portion of the casing or compart-Figure 5 is an end view of Figure 4. ment B, a collecting hopper 22 isprovided by the Figure 6 is a detail of a portion of the appabottom wallof the casing for the surplus abrasive ratus. material and by means ofthe air nozzle 23 which Figure '7 is an enlarged cross section of apiece is connected to a source of air by the pipe 24, of sandpaper, orcloth made in accordance with the surplus abrasive material may be blowngg my method, through the pipe 25 up to a hopper 26 which is The stepsof operation of my machine for positioned above the hopper D outside ofthe making sandpaper and other abrasives consist Compartment B. Theconnection 25 may lead in carrying the fine particles of abrasivematerial, directly t0 the hopper D if'it is so desired, so that such asgarnet, silicon carbidaxilint, aluminum the surplus abrasive materialwhich is not used g oxide or emery, or which may be of any nature up inmy methOd 0f making sandpaper and other ordinarily employed and used forthe making of abrasives in the operation of the apparatus A, sandpaper,emery cloth and like materials, in an will be carried directly back tothe hopper D so even spread out manner to a blower means over that theapparatus A may operate automatically which the abrasive material passeswhile spread and continuous to carry out my method, and pro- I;

ilo

farther away from the belt I I.

vide an abrasive material or sandpaper of the desired nature.

The sheet 28 which is adapted to form the backing or sheet of thesandpaper or other abrasive sheets to be made by my method, travelsautomatically into the compartment fB. passing over the rollers 29 and30, carried by the supporting bracket 3I on the table I0 and from theroller 30 the sheet passes back under the roller 32 and out of thecompartment B. The roller 30 is adjustable on the bracket 3| by means ofthe slots 33 in the bracket bearing 34 for the roller 30, so that thesame maybe moved closer or The roller 32 may be adjustable in the samemanner if it is desired.

The apparatus A operates to carry the fine abrasive particles spread outon the belt II to the blower head C. 'I'he belt I I may be made of anysuitable material so that air may pass through the same from the blowerhead C and yet of such a nature as to carry the abrasive material fromthe hopper D evenly spread out to the backing sheet 28. As the belt IIpasses over the blower head C, the air from the same passingout of theslot I blows the ne particles of abrasive material up against thebacking sheet 28 which has been previously coated with an adhesivematerial, such as glue or varnish, or any other waterproof binder,before entering into the compartment B, and as the fine particles ofabrasive material such as 36 are blown up against the sheet,

they stick to the same by reason of having been shot up like dartsagainst the binder which may be of any material, causing them to projectoutrather than lay down flat against the sheet as in sandpaper andabrasive sheets made by the old method. 'I'he surplus abrasive particles36 will quickly and readily fall away from the backing sheet 28 and begathered in the hopper 22 and automatically carried back to' the hopperI26 or directly to the hopper D.

The sandpaper, emery cloth or similar material formed by my machine,such as is illustrated in Figure 7., has a better cutting quality, ismore effective in its operation, and can be made economically. When theparticles are blown to the backing sheet, either for plain orwater-proof sandpaper or fabric, in the manner set` forthl in my method,they do not collect one against the other but the adhesive surface ofthe backing sheet will just take up the right number of particles tomake the most effective and efficient abrading surface for sandpaper orother similar sheet abrading materials.

In accordance with the patent statutes, I have endeavored to describe myapparatus, and while I believe the apparatus that I have set forth isthe best embodiment of my invention, I desire to have it understood thatthe same may be varied within the scope of the following claims withoutdeparting from the spirit, purpose and intentof my invention.

I claim:

l. The new article of manufacture in apparatus for making sandpaper oremeryy cloth, comprising, a `hopper for abrasive particles, an openingfrom said hopper to feed a thinlayer of the abrasive particles out ofsaid hopper, an endless belt adapted to pick up the thin layer ofabrasive particles, a blower beneath said endless belt adapted to blowthe abrasive particles off of said belt, means for adjustably carryingthe exible backing sheet of the sandpaper or the like with a coat ofadhesive over the surface thereof exposed at a point adjacent saidblower and endless carrier, whereby the abrasive particles carried bysaid belt are blown by said blower into the surface of the adhesive onthe flexible sheet to automatically coatthe surface of the sheet withthe abrasive particles standing out individually one from the other.

2. The new article of manufacture in apparatus for making sandpaper oremery cloth comprising, a hopper for abrasive particles, an opening fromsaid hopper to feed a thin layer of the abrasive particles out of saidhopper, an endless belt adapted to pick up the thin layer of abrasiveparticles, a blower beneath said endless belt adapted to blow theabrasive particles off of said belt, means for adjustably carrying theflexible backing sheet of the sandpaper or the like with a coat ofadhesive over the surface thereof exposed at a point adjacent saidblower and endless carrier, whereby the abrasive particles carried bysaid belt are blown by said blower into the surface of the adhesive onthe flexible sheet to automatically coat the surface of the sheet withthe abrasive particles standing out individually one from the other, ahopper for receiving surplus abrasive particles from said endless belt,and means for pneumatically conveying said surplus abrasive particlesfrom said last-mentioned hopper to said first-mentioned hopper.

3. The new article of manufacture in apparatus for making sandpaper oremery cloth comprising, a hopper for abrasive particles, an opening fromsaid hopper t'o feed a thin layer of the abrasive particles out of saidhopper, an endless belt adapted to pick up the thin layer of abrasiveparticles, a blower beneath said endless belt adapted to blow ltheabrasive particles oil of said belt, means for adjustably carrying theflexible backing sheet of the sandpaper or the like with a coat ofadhesive over the surface thereof exposed at a point adjacent saidblower and endless carrier, whereby the abrasive particles carried bysaid belt are blown by said blower into the surface of the adhesive onthe flexible sheet to automatically coat the surface of the sheet withthe abrasive particles standing out individually one from the other, ahopper for receiving surplus abrasive particles from said endless belt,means for pneumatically conveying said surplus abrasive particles fromsaid last-mentioned hopper to said first-mentioned hopper, and a Wallstructure enclosing said endless belt, said blower, and carrying meansfor the flexible backing sheet, a portion of said wall structure formingsaid hopper for the surplus abrasive particles received from saidendless belt.

WALKER BURNS.

